Research reveals why women experience worse side effects from weight loss drugs

A new report has uncovered significant biological differences between men and women in their response to popular weight loss medications like Ozempic and Zepbound, according to a recent study.

The report provides insights into why female patients, who make up 70 per cent of those taking GLP-1 drugs, experience more severe side effects despite achieving greater weight loss results.

With obesity affecting two billion people worldwide and the treatment market projected to reach $200 billion by 2031, these findings could change how medications are prescribed to millions of patients.

The study showed that women experience 2.5 times higher rates of nausea and vomiting compared to men when taking GLP-1 medications.

Researchers identified a biological explanation: female mice have nearly double the GLP-1 receptor expression in brain regions associated with nausea.

“This isn’t just about improving GLP-1 drugs – it’s about rethinking how we design future therapies for real-world patients from the start,” said David Tingley, co-founder and CEO of Olio Labs, which published the research this week,

The findings suggest that personalised dosing based on a woman’s menstrual cycle could reduce side effects and discontinuation rates.

Researchers found that higher oestrogen levels correlate with more severe side effects, highlighting the role hormones play in medication response.

Founded in 2023 by neuroscientists and computational biologists, Olio Labs takes a different approach to drug development by focusing on whole-body systems rather than individual molecules.

Their Combination Design Engine (CoDE) platform analyses human medical records, biological data, and neural circuit maps to develop treatments tailored to specific populations.

Patricia Martin, Olio Labs advisor and former COO of Lilly Diabetes, said the company’s methodology combines a computational approach with validated preclinical models and real patient data to develop better treatments for specific populations.

“Their patient-first approach has potential to advance personalised medicine,” she said.

The company has secured £3.6m in funding from investors including Boom Capital, Overwater Ventures, Pioneer Fund, and Y Combinator.

“Obesity is one of the largest problems facing healthcare systems today, and Olio’s research will help millions of women have a better solution without the debilitating side effects,” said Kristina Simmons, founder and managing partner of Overwater Ventures.

As the obesity epidemic continues to grow globally, this research highlights the need for sex-specific approaches to medication development and administration.

This could mark a shift in how drugs are designed and prescribed in the future.